The program I use to edit OpenCPN
xml and gpx files is a "structured text editor" used by programmers, but it works on everything using "Open With" without any tweeking. It is free and very small to download, and runs on Win-anything.
Scintilla and SciTE
I have a copy if you have trouble downloading.
Your friends should look in the OpenCPN data folder and try to find the navobj.xml (.1, .2, .3, which are older and older backups of your primary file, which is navobj.xml). You CAN just rename navobj.xml to something .gpx and pretty much install it as a temporary layer and OpenCPN, to look over what's there, without editing the raw text.
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